The present invention relates to an apparatus which conveys a belt-like tire component member to a shaping drum in a tire shaping process.
In manufacturing a tire, a rubber belt-like member being cut in a predetermined length as a tire component member is fed toward a shaping drum by a conveyor belt, and subsequently wound at a predetermined outer peripheral portion of the drum to be shaped (For example, refer to the Japanese Laid-Open Patent Publication No. 02-22040 (1990)).
The belt-like member is, first of all, regulated in its widthwise location on the conveyor belt by being sandwiched from both sides by, for example, a pair of guide members which are mutually shiftable in expanding and contracting directions, then subsequently conveyed to the shaping drum by the conveyor belt. In this instance, by driving the shaping drum and the belt conveyor at speeds of constant ratio, the belt-like member is wound around the shaping drum as being appropriately elongated in a longitudinal direction, then the front and rear ends of the belt-like member coincide with each other when finished to be wound.
However, the running speed of the conveyor belt is controlled by controlling a rotational speed of a driving drum (pulley) on which the conveyor belt is wound. Therefore when slippage occurs between the drum and conveyor belt, the belt conveyor no longer runs at a predetermined speed no matter how the rotational speed of the driving drum is accurately controlled to be the predetermined ratio with respect to the rotational speed of the shaping drum. As a result, there is an error in a feeding amount of the belt-like member conveyed together with the conveyor belt. Therefore, the front end and the rear end of the belt-like member on the shaping drum fail to coincide, causing the defect of connecting portion.
Furthermore, when the conveyor belt shifts in a widthwise direction with respect to the driving drum, it will likely result in a zigzag-shaped wound up condition even if the belt-like member is correctly located on the conveyor belt and conveyed to the shaping drum as maintaining its configuration.
On the other hand, when the belt-like member is regulated in its widthwise location on the conveyor belt as explained in the forgoing description, it is desired that the belt-like member easily slides in a widthwise direction on the conveyor belt. When the belt-like member is conveyed, it is desired that the belt-like member does not slide in both the widthwise direction and the longitudinal direction with respect to the conveyor belt.
If the belt-like member does not slide uniformly on the belt along the whole contact surface between the belt-like member and the conveyor belt in the case that the belt-like member is regulated its widthwise location, for example the side edge of the belt-like member is bent by being pushed by the guide member, therefore it is difficult to achieve accurate locating of the belt-like member.
Moreover, if the belt-like member shifts with respect to the conveyor belt in the widthwise direction when conveyed, the feeding position to the shaping drum varies and, consequently, the belt-like member is wound in the zigzag-shape. On the contrary if the belt-like member shifts with respect to the conveyor in the longitudinal direction, amount of the above-described elongation varies and therefore the front end and the rear end fail to coincide when finished to be wound.